Parallel plate method

In the parallel-plate method, the heat flux downward is measured hy a fluxmeter under which the thermal bond material and the molten salt of interest are located. Because the thermal transfer is only conductive if the thermal contacts are perfect, the balance of heat flow through the... 

ASTM has, in addition to the parallel plate method of D926, standardized a development of the Defo test in DIN 53514 which is designated D604928. 

ISO 7323 1985/Cor 1, 2003. Determination of plasticity number and recovery number -Parallel plate method. 

ASTM D926,2002. Plasticity and recovery (Parallel plate method). 

Though the parallel plate method is described here, cone and plate options are also available. These will more accurately describe the shear stress dependence of the material if that is the experimental goal. 

Martin and Lang, by the parallel plate method, found for water at 7°-60 and 1 atm. kx 103=1 394(1+0 00230. The thermal conductivity of water was measured to 270° by Schmidt and Sellschopp it has a maximum at 130°. Mohanty connected k for water with the degree of association. 

Verifiable single continuous nanofibers can be fabricated by the parallel plate method. Increasing the maximum length of fibers that can be collected across... 

D926 Standard test method for rubber property Plasticity and recovery (parallel plate method). Annual Book of. ASTM Standards. Vol, 09.01. 1996, p. 163. 

Blocking of plastic film can be determined by a parallel plate method. Several devices and sample assemblies are described in the standard, ranging from very simple equipment based on a modified technical balance in which one arm is attached to a parallel assembly of tested samples, and the other arm has a liquid dispensed from a buret to apply a load sufficient to separate two surfaces. Also, an electromechanical device is described. The ISO standard has a similar title but a different principle of measurement. 

ASTM D3354-96 Standard Test Method for Blocking Load of Plastic Film by the Parallel Plate Method. 

Figure 44 Schematic illustration showing the basic configuration for blocking load measurement by the parallel plate method.

Wlien an electrical coimection is made between two metal surfaces, a contact potential difference arises from the transfer of electrons from the metal of lower work function to the second metal until their Femii levels line up. The difference in contact potential between the two metals is just equal to the difference in their respective work fiinctions. In the absence of an applied emf, there is electric field between two parallel metal plates arranged as a capacitor. If a potential is applied, the field can be eliminated and at this point tire potential equals the contact potential difference of tlie two metal plates. If one plate of known work fiinction is used as a reference electrode, the work function of the second plate can be detennined by measuring tliis applied potential between the plates [ ]. One can detemiine the zero-electric-field condition between the two parallel plates by measuring directly the tendency for charge to flow through the external circuit. This is called the static capacitor method [59]. 

A variety of studies can be found in the literature for the solution of the convection heat transfer problem in micro-channels. Some of the analytical methods are very powerful, computationally very fast, and provide highly accurate results. Usually, their application is shown only for those channels and thermal boundary conditions for which solutions already exist, such as circular tube and parallel plates for constant heat flux or constant temperature thermal boundary conditions. The majority of experimental investigations are carried out under other thermal boundary conditions (e.g., experiments in rectangular and trapezoidal channels were conducted with heating only the bottom and/or the top of the channel). These experiments should be compared to solutions obtained for a given channel geometry at the same thermal boundary conditions. Results obtained in devices that are built up from a number of parallel micro-channels should account for heat flux and temperature distribution not only due to heat conduction in the streamwise direction but also conduction across the experimental set-up, and new computational models should be elaborated to compare the measurements with theory. 

When bounding walls exist, the particles confined within them not only collide with each other, but also collide with the walls. With the decrease of wall spacing, the frequency of particle-particle collisions will decrease, while the particle-wall collision frequency will increase. This can be demonstrated by calculation of collisions of particles in two parallel plates with the DSMC method. In Fig. 5 the result of such a simulation is shown. In the simulation [18], 2,000 representative nitrogen gas molecules with 50 cells were employed. Other parameters used here were viscosity /r= 1.656 X 10 Pa-s, molecular mass m =4.65 X 10 kg, and the ambient temperature 7 ref=273 K. Instead of the hard-sphere (HS) model, the variable hard-sphere (VHS) model was adopted in the simulation, which gives a better prediction of the viscosity-temperature dependence than the HS model. For the VHS model, the mean free path becomes ... 

To examine the details of the structure of flames in channels under quenching conditions, numerical methods were used. Two-dimensional CFD simulation of a propane flame approaching a channel between parallel plates was carried out using the FLUENT code [25]. The model reproduced the geometry of the real channels investigated experimentally. Close to the quenching limit, the burning velocity, dead space, and radius of curvature of the flames were all close to the experimental values. 

In the laser flash method, a melt of interest is placed between two parallel plates. The upper plate is heated stepwise and the thermal diffusiv-ity is measured from the rise in temperature. The specific design for molten materials and especially slags employed by Ohta et al. is based on the differential three-layer technique utihzing a special cell that can be accommodated in the system. A schematic diagram of the principle of the measurement section is shown in Fig. 31. A laser pulse irradiates the upper (platinum) crucible and the temperature response of the surface of the lower platinum crucible is observed, a liquid specimen being sandwiched between the two. 

The radio-frequency glow-discharge method [30-34] has been the most used method in the study of a-C H films. In this chapter, it is referred to as RFPECVD (radio frequency plasma enhanced chemical vapor deposition). Film deposition by RFPECVD is usually performed in a parallel-plate reactor, as shown in Figure 1. The plasma discharge is established between an RF-powered electrode and the other one, which is maintained at ground potential. The hydrocarbon gas or vapor is fed at a controlled flow to the reactor, which is previously evacuated to background pressures below lO"" Torr. The RF power is fed to the substrate electrode... 

ASTM, Standard Test Method for Determination of External Loading Characteristics of Plastic Pipe by Parallel-Plate Loading, ASTM D2412-02, American Society for Testing and Materials, West Conshohocken, PA, 2002. 

Method involves placing a specimen between parallel plate capacitors and applying a sinusoidal voltage (frequencies ranging from 1 mHz to 1 MHz) to one of the plates to establish an electric field in the specimen. In response to this field, a specimen becomes electrically polarized and can conduct a small charge from one plate to the other. Through measurement of the resultant current, the dielectric constant and dielectric loss constant for a specimen can be measured. The sharp increases in both the dielectric constant and the dielectric loss constant during a temperature scan are correlated with the occurrence of Tg... 

Penney and Lynch (P2, Method No. 2) passed an aerosol between two parallel plates with an adjustable potential across them. The collection efficiency achieved is a measure of the average electrostatic mobility of the particles. 

If both electrodes have to be made of materials, that are available only as foils or sheets or are not machinable, or for example, for materials, such as graphite felt, a cell design like the one in Fig. 9 is not realizable. Inlet and outlet systems have to be integrated in the electrolyte compartments. The parallel-plate and frame design of a laboratory flow-trough cell in Fig. 10 consists of easy-to-produce parts, using the fixing method for PTFE tubes in Fig. 4. 

ISO 6721-8 1997 Plastics - Determination of dynamic mechanical properties - Part 8 Longitudinal and shear vibration - Wave-propagation method ISO 6721-10 1999 Plastics - Determination of dynamic mechanical properties - Part 10 Complex shear viscosity using a parallel-plate oscillatory rheometer ISO 9311-2 2002 Adhesives for thermoplastic piping systems - Part 2 Determination of shear strength... 

Note 4 Some experimental methods, such as capillary flow and flow between parallel plates, employ a range of shear rates. The value of tj evaluated at some nominal average value of Y is termed the apparent viscosity and given the symbol /app. It should be noted that this is an imprecisely defined quantity. 

Later, when the Brent stabilization trains were commissioned. a similar, less severe foaming tendency was observed The phased commissioning program allowed installation and assessment of the performance of parallel plates (Dixon plates) in the separators as a method of breaking down foam. 

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